[PATCH] Diff-tree-helper take two.
This reworks the diff-tree-helper and show-diff to further make external
diff command interface simpler.
These commands now honor GIT_EXTERNAL_DIFF environment variable which
can point at an arbitrary program that takes 7 parameters:
name file1 file1-sha1 file1-mode file2 file2-sha1 file2-mode
The parameters for an external diff command are as follows:
name this invocation of the command is to emit diff
for the named cache/tree entry.
file1 pathname that holds the contents of the first
file. This can be a file inside the working
tree, or a temporary file created from the blob
object, or /dev/null. The command should not
attempt to unlink it -- the temporary is
unlinked by the caller.
file1-sha1 sha1 hash if file1 is a blob object, or "."
otherwise.
file1-mode mode bits for file1, or "." for a deleted file.
If GIT_EXTERNAL_DIFF environment variable is not set, the
default is to invoke diff with the set of parameters old
show-diff used to use. This built-in implementation honors the
GIT_DIFF_CMD and GIT_DIFF_OPTS environment variables as before.
Signed-off-by: Junio C Hamano <junkio@cox.net>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/diff-tree-helper.c b/diff-tree-helper.c
index 293e00b..bcf89a5 100644
--- a/diff-tree-helper.c
+++ b/diff-tree-helper.c
@@ -1,3 +1,6 @@
+/*
+ * Copyright (C) 2005 Junio C Hamano
+ */
#include "cache.h"
#include "strbuf.h"
#include "diff.h"
@@ -17,15 +20,22 @@
return 0;
}
-static int parse_oneside_change(const char *cp, unsigned char *sha1,
- char *path) {
+static int parse_oneside_change(const char *cp, struct diff_spec *one,
+ char *path)
+{
int ch;
- while ((ch = *cp) && '0' <= ch && ch <= '7')
- cp++; /* skip mode bits */
+
+ one->file_valid = one->sha1_valid = 1;
+ one->mode = 0;
+ while ((ch = *cp) && '0' <= ch && ch <= '7') {
+ one->mode = (one->mode << 3) | (ch - '0');
+ cp++;
+ }
+
if (strncmp(cp, "\tblob\t", 6))
return -1;
cp += 6;
- if (get_sha1_hex(cp, sha1))
+ if (get_sha1_hex(cp, one->u.sha1))
return -1;
cp += 40;
if (*cp++ != '\t')
@@ -34,31 +44,20 @@
return 0;
}
-#define STATUS_CACHED 0 /* cached and sha1 valid */
-#define STATUS_ABSENT 1 /* diff-tree says old removed or new added */
-#define STATUS_UNCACHED 2 /* diff-cache output: read from working tree */
-
static int parse_diff_tree_output(const char *buf,
- unsigned char *old_sha1,
- int *old_status,
- unsigned char *new_sha1,
- int *new_status,
+ struct diff_spec *old,
+ struct diff_spec *new,
char *path) {
const char *cp = buf;
int ch;
- static unsigned char null_sha[20] = { 0, };
switch (*cp++) {
case '+':
- *old_status = STATUS_ABSENT;
- *new_status = (memcmp(new_sha1, null_sha, sizeof(null_sha)) ?
- STATUS_CACHED : STATUS_UNCACHED);
- return parse_oneside_change(cp, new_sha1, path);
+ old->file_valid = 0;
+ return parse_oneside_change(cp, new, path);
case '-':
- *new_status = STATUS_ABSENT;
- *old_status = (memcmp(old_sha1, null_sha, sizeof(null_sha)) ?
- STATUS_CACHED : STATUS_UNCACHED);
- return parse_oneside_change(cp, old_sha1, path);
+ new->file_valid = 0;
+ return parse_oneside_change(cp, old, path);
case '*':
break;
default:
@@ -66,191 +65,36 @@
}
/* This is for '*' entries */
- while ((ch = *cp) && ('0' <= ch && ch <= '7'))
- cp++; /* skip mode bits */
+ old->file_valid = old->sha1_valid = 1;
+ new->file_valid = new->sha1_valid = 1;
+
+ old->mode = new->mode = 0;
+ while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
+ old->mode = (old->mode << 3) | (ch - '0');
+ cp++;
+ }
if (strncmp(cp, "->", 2))
return -1;
cp += 2;
- while ((ch = *cp) && ('0' <= ch && ch <= '7'))
- cp++; /* skip mode bits */
+ while ((ch = *cp) && ('0' <= ch && ch <= '7')) {
+ new->mode = (new->mode << 3) | (ch - '0');
+ cp++;
+ }
if (strncmp(cp, "\tblob\t", 6))
return -1;
cp += 6;
- if (get_sha1_hex(cp, old_sha1))
+ if (get_sha1_hex(cp, old->u.sha1))
return -1;
cp += 40;
if (strncmp(cp, "->", 2))
return -1;
cp += 2;
- if (get_sha1_hex(cp, new_sha1))
+ if (get_sha1_hex(cp, new->u.sha1))
return -1;
cp += 40;
if (*cp++ != '\t')
return -1;
strcpy(path, cp);
- *old_status = (memcmp(old_sha1, null_sha, sizeof(null_sha)) ?
- STATUS_CACHED : STATUS_UNCACHED);
- *new_status = (memcmp(new_sha1, null_sha, sizeof(null_sha)) ?
- STATUS_CACHED : STATUS_UNCACHED);
- return 0;
-}
-
-static int sha1err(const char *path, const unsigned char *sha1)
-{
- return error("diff-tree-helper: unable to read sha1 file of %s (%s)",
- path, sha1_to_hex(sha1));
-}
-
-static int fserr(const char *path)
-{
- return error("diff-tree-helper: unable to read file %s", path);
-}
-
-static char *map_whole_file(const char *path, unsigned long *size) {
- int fd;
- struct stat st;
- void *buf;
-
- if ((fd = open(path, O_RDONLY)) < 0) {
- error("diff-tree-helper: unable to read file %s", path);
- return 0;
- }
- if (fstat(fd, &st) < 0) {
- close(fd);
- error("diff-tree-helper: unable to stat file %s", path);
- return 0;
- }
- *size = st.st_size;
- buf = mmap(NULL, st.st_size, PROT_READ, MAP_PRIVATE, fd, 0);
- close(fd);
- return buf;
-}
-
-static int show_diff(const unsigned char *old_sha1, int old_status,
- const unsigned char *new_sha1, int new_status,
- const char *path, int reverse_diff)
-{
- char other[PATH_MAX];
- unsigned long size;
- char type[20];
- int fd;
- int reverse;
- void *blob = 0;
- const char *fs = 0;
- int need_unmap = 0;
- int need_unlink = 0;
-
-
- switch (old_status) {
- case STATUS_CACHED:
- blob = read_sha1_file(old_sha1, type, &size);
- if (! blob)
- return sha1err(path, old_sha1);
-
- switch (new_status) {
- case STATUS_CACHED:
- strcpy(other, ".diff_tree_helper_XXXXXX");
- fd = mkstemp(other);
- if (fd < 0)
- die("unable to create temp-file");
- if (write(fd, blob, size) != size)
- die("unable to write temp-file");
- close(fd);
- free(blob);
-
- blob = read_sha1_file(new_sha1, type, &size);
- if (! blob)
- return sha1err(path, new_sha1);
-
- need_unlink = 1;
- /* new = blob, old = fs */
- reverse = !reverse_diff;
- fs = other;
- break;
-
- case STATUS_ABSENT:
- case STATUS_UNCACHED:
- fs = ((new_status == STATUS_ABSENT) ?
- "/dev/null" : path);
- reverse = reverse_diff;
- break;
-
- default:
- reverse = reverse_diff;
- }
- break;
-
- case STATUS_ABSENT:
- switch (new_status) {
- case STATUS_CACHED:
- blob = read_sha1_file(new_sha1, type, &size);
- if (! blob)
- return sha1err(path, new_sha1);
- /* old = fs, new = blob */
- fs = "/dev/null";
- reverse = !reverse_diff;
- break;
-
- case STATUS_ABSENT:
- return error("diff-tree-helper: absent from both old and new?");
- case STATUS_UNCACHED:
- fs = path;
- blob = strdup("");
- size = 0;
- /* old = blob, new = fs */
- reverse = reverse_diff;
- break;
- default:
- reverse = reverse_diff;
- }
- break;
-
- case STATUS_UNCACHED:
- fs = path; /* old = fs, new = blob */
- reverse = !reverse_diff;
-
- switch (new_status) {
- case STATUS_CACHED:
- blob = read_sha1_file(new_sha1, type, &size);
- if (! blob)
- return sha1err(path, new_sha1);
- break;
-
- case STATUS_ABSENT:
- blob = strdup("");
- size = 0;
- break;
-
- case STATUS_UNCACHED:
- /* old = fs */
- blob = map_whole_file(path, &size);
- if (! blob)
- return fserr(path);
- need_unmap = 1;
- break;
- default:
- reverse = reverse_diff;
- }
- break;
-
- default:
- reverse = reverse_diff;
- }
-
- if (fs)
- show_differences(fs,
- path, /* label */
- blob,
- size,
- reverse /* 0: diff blob fs
- 1: diff fs blob */);
-
- if (need_unlink)
- unlink(other);
- if (need_unmap && blob)
- munmap(blob, size);
- else
- free(blob);
return 0;
}
@@ -275,28 +119,20 @@
}
/* the remaining parameters are paths patterns */
- prepare_diff_cmd();
-
while (1) {
- int old_status, new_status;
- unsigned char old_sha1[20], new_sha1[20];
+ struct diff_spec old, new;
char path[PATH_MAX];
read_line(&sb, stdin, line_termination);
if (sb.eof)
break;
- if (parse_diff_tree_output(sb.buf,
- old_sha1, &old_status,
- new_sha1, &new_status,
- path)) {
+ if (parse_diff_tree_output(sb.buf, &old, &new, path)) {
fprintf(stderr, "cannot parse %s\n", sb.buf);
continue;
}
- if (1 < ac && ! matches_pathspec(path, av+1, ac-1))
+ if (1 < ac && !matches_pathspec(path, av+1, ac-1))
continue;
- show_diff(old_sha1, old_status,
- new_sha1, new_status,
- path, reverse_diff);
+ run_external_diff(path, &old, &new);
}
return 0;
}
